|Publication number||US6213420 B1|
|Application number||US 09/369,194|
|Publication date||Apr 10, 2001|
|Filing date||Aug 6, 1999|
|Priority date||Aug 6, 1998|
|Also published as||DE19835673A1, EP0978427A1|
|Publication number||09369194, 369194, US 6213420 B1, US 6213420B1, US-B1-6213420, US6213420 B1, US6213420B1|
|Original Assignee||Takata (Europe) Vehicle Safety Technology Gmbh|
|Export Citation||BiBTeX, EndNote, RefMan|
|Patent Citations (12), Referenced by (5), Classifications (6), Legal Events (5)|
|External Links: USPTO, USPTO Assignment, Espacenet|
The invention relates to a safety belt apparatus with an acceleration sensor.
A safety belt apparatus of this kind is known for example from GB 2 131 279. Its principle is based on the fact that an acceleration sensor which is equipped with a sphere as a movable mass has a pawl which is pivotal about a transverse axis and which engages into a tooth at the periphery of a position control ratchet wheel in horizontal movements of the sphere as a result of accelerations or decelerations, through which the position control ratchet wheel, which is connected in a rotationally fixed manner via a transmission to the belt roller, is abruptly braked. Since the belt is drawn further out, the transmission, which is provided between the position control ratchet wheel and the main pawl, experiences a moving out of the main pawl in order that the latter engages into the main ratchet crown and thus stops the drawing out movement of the belt.
A problem in acceleration sensors operating in this manner consists in that the movable mass moves back and forth in the free space surrounding it as a result of the vibrations during normal travel, with the auxiliary pawl also being continually pivoted back and forth. In this it strikes again and again at the outer periphery of the position control ratchet wheel, which leads to disagreeable rattling noises.
The object of the invention consists in providing a safety belt apparatus of the initially named kind in which rattling noises of the acceleration sensor and of the parts connected to it during normal travel are largely forestalled.
The idea of the invention is thus to be seen in providing the pawl at a spring element which damps thrusts which arise during the striking against the position control ratchet wheel to such an extent that the development of rattling noise is at least greatly reduced.
Advantageous further developments are characterised by the path limiting means between the limbs receiving an especial significance.
The invention will be explained in the following in an exemplary manner with reference to the drawings; in these are shown:
FIG. 1 a schematic side view of an advantageous embodiment of a safety belt apparatus in accordance with the invention, with the acceleration sensor and the components cooperating with it being reproduced at a strong magnification.
In accordance with FIG. 1 a safety belt apparatus in accordance with the invention has a seat belt 12 which is wound up on a belt roller 11 to a greater or lesser extent and which leads via a belt lock 28 to a securing point 29 at the vehicle body. A further belt part 12′ extends from the belt lock 28 to a further securing point 30 at the vehicle body. It is thus a matter of a usual three point belt.
Rotationally fixedly connected to the belt roller 11 or to its shaft 31 respectively is a pawl mechanism 32 which has an outwardly movable main pawl 17 which can be moved outwards via a transmission 16, which is only indicated in broken lines, in such a manner that it engages into an inner main ratchet crown 18 which is provided at the periphery of an opening 33 in the vehicle-fixed housing of the belt roller, which is otherwise not illustrated in detail.
Coupled in a rotationally fixed manner to the belt roller shaft 31 via the transmission 16 is a position control ratchet wheel 14 which is coaxial with the main ratchet crown 18 and which is provided at its outer periphery with blocking teeth 34.
At a housing 35 of the belt roller, which is not illustrated in detail, is secured an acceleration sensor 13 which consists of a movable mass 19, which is defined in its freedom of movement in a confinement 27 and which can also be formed as a sphere, and a spring element 20 which is pivotal about a pivotal transverse axis 26 and which had two limbs 20′, 20″ which stand in V shape relative to one another, with the pivotal transverse axis 26 being provided at the apex of the V and extending parallel to the belt roller shaft 31.
The lower, or control limb 20′ is provided with a lower depression 21 which extends upwardly in the manner of a spherical section and into which an upper projection 22 of the movable mass 19, which is correspondingly formed in the shape of a spherical section, engages. The projection 22 can also be formed by the crown of a sphere. In horizontal accelerations and decelerations of the movable mass 19 or tiltings of the vehicle respectively, the projection 22 is displaced within the depression 21 to the one side or the other, with the projection 22 attempting to slide out of the depression 21 and in the process pivoting the V-shaped spring element 20 upwardly about the transverse axis 26 until the auxiliary pawl 15 which is provided at the front end of the upper limb 20″ engages between two teeth 34 of the position control ratchet wheel 14. Through this a clockwise rotational movement of the position control ratchet wheel 14 which arises when the belt 12 is drawn out is stopped. Since the belt roller 11 however continues to rotate when the drawing out of the belt 12 is continued, an actuation of the transmission 16 takes place as a result of the relative movement between the pawl mechanism 32 and the position control ratchet wheel 14, which leads to the moving out of the main pawl 17, which then comes into engagement with a tooth of the main ratchet crown 18, whereupon the further drawing-out movement of the belt 12 is stopped.
Between the ends of the limbs 20′, 20″ which face away from the transverse axis 26 there extends a draw member 23 in the form of a plastic fibre which determines the largest opening angle of the V-shaped spring element 20. This is advantageous because otherwise in the course of the lifetime of a motor vehicle it could happen that the V-angle of the spring element 20 opens through long term deformation and an engagement of the pawl 15 into the outer toothed crown of the position control ratchet wheel 14 could also take place already without a movement of the mass 19. The draw member 23 should consist of a material which does not stretch in the long term.
In addition abutment webs 24, 25 extend from the end regions of the limbs 20′, 20″, in each case in the direction of the other limb. The free end surfaces 24′, 25″ of the two abutment webs 24, 25 end in the non-tensioned state at a distance A which is chosen in such a manner that the spring deflection of the spring element 20 is limited to a value which is sufficient for the desired noise damping. The end surfaces 24′, 25′ preferably extend at an inclination relative to the direction of movement of the abutment webs 24, 25 so that when the end surfaces 24′, 25′ strike one another a certain sliding movement between the end surfaces 24′, 25′ takes place in the presence of a further resilient deformation of the spring element 20. Through this an increased damping is achieved at the end of the spring deflection.
As a result of the design in accordance with the invention, rattling noises are strongly damped, which would otherwise be produced during normal travel by the pivoting back and forth of the movable mass 19 and the V-shaped spring element 20.
The end surfaces 24′, 25′ are placed at an inclination in such a manner that they extend at least substantially parallel to one another.
|Cited Patent||Filing date||Publication date||Applicant||Title|
|US4168810 *||May 22, 1978||Sep 25, 1979||Allied Chemical Corporation||Novel locking mechanism and reel for retractor|
|US4190213 *||Sep 11, 1978||Feb 26, 1980||Nsk-Warner K. K.||Safety belt take-up device|
|US4453681 *||Oct 22, 1982||Jun 12, 1984||Autoliv Ab.||Winder for a safety belt|
|US4483495||Nov 24, 1982||Nov 20, 1984||Repa Feinstanzwerk Gmbh||Mechanism for blocking a roll-up device for safety belts|
|US4760975||Jun 30, 1987||Aug 2, 1988||Gateway Industries, Inc.||Seat belt retractor|
|US4979695 *||Oct 17, 1989||Dec 25, 1990||Nippon Seiko Kabushiki Kaisha||Overlock prevention mechanism for acceleration sensor|
|US5443224 *||Jul 16, 1993||Aug 22, 1995||Alliedsignal Inc.||Emergency locking passenger safety belt mechanisms|
|DE2402921A1||Jan 22, 1974||Aug 28, 1975||Artur Foehl||Traegheitssteuerung|
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|GB2131279A||Title not available|
|WO1987006545A1||Apr 30, 1987||Nov 5, 1987||Autoliv Development Ab||Meshing means, controlled by an inertia body, for toothed control wheels in locking devices for vehicle safety belts|
|Citing Patent||Filing date||Publication date||Applicant||Title|
|US6732969 *||Nov 27, 2001||May 11, 2004||Takata Corporation||Seatbelt retractor|
|US7455256 *||Apr 18, 2005||Nov 25, 2008||Key Safety Systems, Inc.||Seatbelt retractor having a cushioned sensor actuator|
|US20020066818 *||Nov 27, 2001||Jun 6, 2002||Hiromasa Tanji||Seatbelt retractor|
|US20050248144 *||Sep 14, 2004||Nov 10, 2005||John Bell||Vehicle acceleration sensor for seat belt retractor|
|US20060231666 *||Apr 18, 2005||Oct 19, 2006||Key Safety Systems, Inc.||Seatbelt retractor having a cushioned sensor actuator|
|U.S. Classification||242/384, 242/384.5|
|International Classification||B60R22/40, B60R22/48|
|Aug 6, 1999||AS||Assignment|
Owner name: TAKATA (EUROPE) VEHICLE SAFETY TECHNOLOGY GMBH, GE
Free format text: ASSIGNMENT OF ASSIGNORS INTEREST;ASSIGNOR:KOPETZKY, ROBERT;REEL/FRAME:010157/0111
Effective date: 19981105
|Sep 27, 2004||FPAY||Fee payment|
Year of fee payment: 4
|Oct 20, 2008||REMI||Maintenance fee reminder mailed|
|Apr 10, 2009||LAPS||Lapse for failure to pay maintenance fees|
|Jun 2, 2009||FP||Expired due to failure to pay maintenance fee|
Effective date: 20090410